• The KIPS Transactions:PartC
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• v.13C no.4 s.107
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• pp.389-396
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• 2006

P2P(Peer To Peer) system, a most attractive file sharing system, is the largest channel of contents distribution and it takes 50% of network traffic. But P2P systems are infamous for used to illegal contents distribution channel not only in music industry, but also in movie industry. But, DRM(Digital Right Management) enabled P2P models are not suggested until now that interrupting illegal contents distribution and keeping advantage of P2P. So in this paper, we suggest a DRM enabled P2P model that can support distributed processing ability and high scalability with no modification in exist P2P model or architecture.

• Journal of Powder Materials
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• v.13 no.1 s.54
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• pp.39-45
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• 2006

The $Al/SiC_p$ particle reinforced composite fabricated by a powder-in sheath rolling (PSR) method was severely. deformed by the accumulative roll-bonding (ARB) process. The ARB process was performed up to 8 cycles at ambient temperature without lubricant. The ARBed composite exhibited an ulbricant. grained structure similar to the other ARBed bulky materials. Tensile strength of the composite increased gradually with the number of ARB cycles, but from the 6th cycle it rather decreased slightly. These characteristics of the composite were somewhat different from those of Al powder compact fabricated by the same procedures. The difference in microstructure and mechanical properties between Al powder compact and the composite was discussed.

• The Korean Journal of Zoology
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• v.21 no.2
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• pp.67-75
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• 1978

The auther investigated the distribution and seasonal variations of Copepods and Branchiopods in Myeongam Lake located in Cheongju City, Chungchungbuk Do. Air and Water temperature, pH, and the amount of dissolved oxygen were also measured eleven times from July 29 to November 5, 1977. The results obtained are as follows: 1. The mean values of air and water temperature, pH, and dissolved oxygen during the investigation period were $25^{\circ}C , $23.7^{\circ}C, 6.86, and 10.75 ppm, respectively. 2. The total number of species collected in this lake were 13 species (1) thermocyclops taihokuensis (Harada) (2) Thermocyclops hyalinus (Rehberg) (3) Mesocyclops leuckarti (Claus) (4) Diacyclops disjunctus (Thallwitz) (5) Paracyclops fimbriatus (Fischer) (6) Cyclops sp. a (7) Cyclops sp. b (8) Diaphanosoma brachyurum (Lievin) (9) Daphnia pulex Leydig (10) Daphnia longispina (O. F. Muller) (11) Daphnia sp. (12) Moina dubia De Guerne et Richard (13) Chydorus sphaericus (O. F. Muller) 3. Among these species, 4 species (1, 3, 8, 10) were collected continually throughout the investigation period. 4. The dominant species was Diaphanosoma brachyurum during the investigation period.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.845-851
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• 2002

The synthesis of the intramolecular donor - stabilized silyl and germyl complexes of the type ($Cab^c.p) MMe_2X$ (2a:M=Si, X=Cl;2b;M= Ge, X=Cl;2e;M=Si,X=H) was achieved by the reaction of $LiCab^c,p$ (1) with $Me_2SiClX$ and $Me_2GeCl_2$ respectively. The intramolecular M←P interacion in 2a-2c is provided by $^1H$, $13^C.$, $31^P$ and $29^Si$ NMR spectroscopy. The salt elimination reactions of dichlorotetramethyldisilane and -digermane with 1 afforded the $bis(\sigma-carboranylphosphino)disilane$ and disgermane [$(Cab^C.P)MMe_2]_2(4a;M$ = Si;4b: M=Ge). The oxidative addition reaction of 4a-4b with $pd_2(dba)_3CHCl_3afforded$ the bis(silyl)-and bis(germyl)-palladium complexes. The chloro-bridged dipalladium complexes were obtained by the reaction of 2a-2b with $pd_2(dba)_3CHCl_3$ The crystal structures of 5a and 7b were determined by X-ray structural studies.

• Journal of the Korean Chemical Society
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• v.13 no.2
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• pp.187-193
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• 1969

As part of an extensive program on the microbiological oxidation of hydrocarbons, reaction conditions and nutrients consumption of candida lipolytica grown on alkane as carbon source were studied. For optimum growth of yeast, the conditions of pH 5, temperature $30^{\circ}C$, carbon number $C_{16}$& $C_{18}$aeration 25.6 1/l/hr, agitation 3000 r.p.m., hydrocarbon concentration 10% were obtained. Carbon and nitrogen balance related to these conditions were also investigated. In the course of this investigation, some significant effects of pH and carbon number of hydrocarbon variation were observed.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.473-474
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• 2006

Boron Phosphide films were deposited on (111) Si substrate at $650^{\circ}C$, by the reaction of B2H6 with PH3 using APCVD. N2 was carried out as carrier gas. The optimal gas rates were $20\;m{\ell}/min$ for B2H6, $60\;m{\ell}/min$ for PH3 and $1\;{\ell}/min$ for N2. After as grown the films were insitu annealed for 1hour in N2 ambient at $550^{\circ}C$ and measured. The measurement of AFM shows that the RMS is $29.626{\AA}$ for the reaction temperature at $650^{\circ}C$. The measurement of XRD shows that the films have the orientation of (101). Also, the measurement of AES is shown that the films have B13P2 stoichiometry.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.192-201
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• 2019

While a fairly large amount of organic matter is produced daily via phytoplankton photosynthesis in Lake Paldang, South Korea, knowledge of the role of algal-derived organic matter (OM) as a refractory OM source is not adequate. To understand the contribution of algal-derived OM to the refractory pool, biodegradation experiment and $KMnO_4$ oxidation experiment were conducted for 60 days using $^{13}C$ and $^{15}N$ labeled natural phytoplankton assemblage. The assemblage was collected from Lake Paldang on May 20, 2010. The photosynthetically produced total organic carbon ($TO^{13}C$), particulate organic carbon ($PO^{13}C$), and particulate nitrogen ($P^{15}N$) remained at 26%, 20%, and 17% of the initial concentrations, respectively, in the form of non-biodegradable organic matter. In addition, 12% and 38% of $PO^{13}C$ remained after $KMnO_4$ treatment on Day 0 and 60, respectively. These results indicate that photosynthetic products could be an important source of refractory organic matter after microbial degradation. Moreover, the microbially transformed algal-derived OM could contribute to the oxidation rate of the chemical oxygen demand.

• Mycobiology
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• v.41 no.3
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• pp.139-144
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• 2013

Makgeolli is a traditional cloudy-white Korean rice wine with an alcohol content of 6~7%. The present study investigated the morphological characteristics, carbon-utilizing ability, fatty acid composition, alcohol resistance, glucose tolerance, and flocculence of Saccharomyces cerevisiae Y98-5 and Pichia anomala Y197-13, non-S. cerevisiae isolated from Nuruk, which is used in brewing Makgeolli. Similar morphological characteristics were observed for both isolated wild yeast strains; and the carbon source assimilation of Y197-13 differed from that of other P. anomala strains. Strain Y197-13 was negative for D-trehalose, mannitol, arbutin, I-erythritol, and succinic acid. The major cellular fatty acids of strain Y197-13 included C18:2n6c (33.94%), C18:1n9c (26.97%) and C16:0 (20.57%). Strain Y197-13 was Crabtree-negative, with 60% cell viability at 12% (v/v) ethanol. The flocculation level of strain Y197-13 was 8.38%, resulting in its classification as a non-flocculent yeast.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.120-126
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• 1989

The Kinetics of hydrolysis of styrylphenylsulfone derivatives in 50% methanol-water at 25$^{\circ}$C and ionic strength of 0.10 was investigated by UV spectrophotometry in the pH range of 0.0-14.0. The rate equations, which can be applied over a wide pH range, were obtained. The Hammett rho constants for the hydrolysis are 1.85 at pH 7.0 and 1.54 at pH 13.0, respectively. On the basis of the evidence, it is proposed that the general base-catalysis occurs in the hydrolysis of styrylphenylsulfone derivatives; above pH 11.0, Michael type nucleophilic addition take place, while below pH 9.0, the reaction is initiated by addition of water and from pH 9.0 to pH 11.0 these two reactions occur com-petitively.

• The Korean Journal of Rehabilitation Nursing
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• v.8 no.1
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• pp.13-19
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• 2005

Purpose: This study was aimed to identify the effects of group exercise on physiological functions in Elderly. Method: The design of research was one group pretest-posttest design. The subjects were sixty two elderly women persons over sixty years old to live in C-GUN, The exercise period was 12-weeks and frequency was three times per week. the exercise duration was sixty minites. In order to evaluate the effect of exercise, we measured %body fat, fat mass(FM), fat free mass(FFM), body mass index(BMI), body metabolic rate(BMR), Total Cholesterol(TC), Triglyceride(TG), high density lipoprotein-c(HDL-C), low density lipoprotein-c(LDL-C) before and after the 12 week's group exercise program. The data analyzed by the paired t-test using SPSS package. Result: There was significant difference in FFM(p=.000), BMR(p=.000), HDL-C(p=.010). There was no significant difference in weight(p=.122), %body fat(p=.062),, FM(p=.704), BMI(p=.136), TC(p=.125), TG(p=.064), LDL-C(p=.575) Conclusion: This group exercise for elderly women can be recommended as an effective nursing intervention for elderly women in a community.